1. Field of the Invention
This invention relates to sound reproduction devices, and in particular to a system for producing a multi-mode ambient soundstage in a home theater environment.
2. Related Art
Sound reproduction devices such as loudspeakers are utilized in a broad range of applications in many distinct fields of technology including the consumer and industrial fields. Sound reproduction devices utilize a combination of mechanical and electrical components to convert received electrical signals, representative of the sound, into mechanical energy that produces sound pressure waves in an ambient sound field corresponding to the received electrical signals.
In today's society, the utilization of home theater systems is increasing as consumers attempt to reproduce the cinema and concert theater experiences within their homes. As a result, manufactures have produced numerous types of audio and video systems capable of reproducing different types of theater environments within the home of a consumer. These theater environments include analog and digital surround sound, Dolby® digital sound, digital theater System (“DTS”), extended DTS (“DTS-ES”), THX® and other digital signal processing (“DSP”) modes.
The audio and video systems capable of producing these theater environments include numerous electronic components and loudspeakers. Typically the systems include from six to eight loudspeakers to produce various ambient sound fields. As an example of a cinema theater environment, a 5.1 type cinema theater system includes a pair of left and right front loudspeakers, a center channel loudspeaker, a pair of left surround loudspeakers and a subwoofer loudspeaker. A 6.1 type cinema theater system includes a pair of left and right front loudspeakers, a center channel loudspeaker, a pair of left surround loudspeakers, a back surround sound loudspeaker and a subwoofer loudspeaker. And a 7.1 type cinema theater system includes a pair of left and right front loudspeakers, a center channel loudspeaker, a pair of left surround loudspeakers, a pair of right and left back surround sound loudspeakers and a subwoofer loudspeaker.
A problem with these audio and video systems is that the surround sound loudspeakers in these systems are either dipolar or bipolar and are placed external to the wall surfaces of a room containing the system. As a result, mass consumer acceptance of some of these types of systems is relatively low because the surround loudspeaker are bulky, visually unappealing and tend to force a consumer to utilize the room exclusively for a cinema home theater system. Attempts have been made at utilizing in-wall and in-ceiling loudspeakers. However, it is difficult to produce an ambient sound field equivalent to the external surround sound loudspeakers with a sound reproduction system that is imbedded and flush within the wall and ceiling surfaces because the dispersion from its locations within walls are obscured by the wall and ceiling surfaces. Typically, unless the loudspeaker is capable of producing an angled pattern for the sound, the loudspeaker will be obstructed and will not be able to create the type of sound stage that is desirable for accurate sound reproduction within the home theater system. Therefore, there is a need for a sound reproduction system that is capable of producing an ambient sound field equivalent to external surround sound loudspeakers while being imbedded in the wall and/or ceiling and being flush with the wall and ceiling surfaces of a room.
An additional problem with these audio and video systems is that typically rooms are arranged differently from home-to-home. Some rooms are small and have four walls while others may be large and only have three, or two, main walls that are compatible for placing loudspeakers. Thus, there is also a need for a sound reproduction system that is capable of producing an ambient sound field equivalent to external surround sound loudspeakers while being imbedded in various locations on the walls and ceilings of a room, while at the same time being flush with the wall and ceiling surfaces of the room.
Still another problem is that generally audio and video systems that are optimized for a cinema environment are different than audio systems that are optimized for a music listening environment. Typically, cinema environments require dipolar or bipolar surround sound loudspeaker configurations to produce diffuse ambient sound fields, while music listening environments require direct radiating type loudspeakers to accurately reproduce the music. Thus there is also a need for a sound reproduction system that is capable of producing an ambient sound field for both cinema and music environments equivalent to external surround sound loudspeakers while being imbedded in the wall and/or ceiling and being flush with the wall and ceiling surfaces of a room.